374 Prakt. Met. Sonderband 46 (2014) 
facilities, plants, transport systems etc., high emphasize has to be placed on risk 
avoidance which is based on the understanding of corrosive mechanics. 
Fig. 1: Corroded surfaces are characterized by steep flanks Conve 
and varying reflection properties 
mean 
repre: 
depth 
3. FOCUS-VARIATION FOR OPTICAL 3D MEASUREMENT IN THE MICRO surfac 
AND NANO RANGE with re 
The optical InfiniteFocus system based on the principle of Focus-Variation meets all 
requirements for corrosion analysis. Measurements reach a vertical resolution of up to 4. TH 
10nm even at steep flanks and strongly varying reflection properties. Additionally, the 
entire surface topographic information is captured in combination with its registered color The c 
information. Both, the topographic and color information are reaistered to the 3D data file. depth 
inform 
inforrr 
Using 
reach 
high \ 
Additi 
Fig. 2: Topographic and color information 
are registered to a 3D data file 
The high resolution 3D system is often used to analyze mechanically influenced corrosion, 
e.g. stress corrosion cracking, corrosion fatigue cracking or erosion corrosion. Pitting 
corrosion, crevice corrosion and selective corrosion are further fields of interest. Metallic 
components such as stainless steels, nickel-base alloys, titanium or aluminium alloys are 
easily measured. Due to the surface analysis, corrosive mechanics and attacks can be 
better understood. In terms of measuring degradation coming along with e.g. erosion 
corrosion, profile analysis to measure depth and area analysis to show the deepest void 
are the most distinctive characteristics.